1. Field of the Invention
The present invention relates to an automatic wheel attachment apparatus for automatically attaching wheels to an automotive body, and more particularly to a robot in such an automatic wheel attachment apparatus for reorienting a wheel attachment member or hub, phasing wheel attachment bolts on the whee attachment member, and positionally detecting the wheel attachment member.
2. Description of the Relevant Art
One conventional apparatus for automatically mounting wheels on an automotive body is disclosed in Japanese Laid-Open Patent Publication No. 60-42521 published Mar. 26, 1985.
The disclosed automatic wheel attachment apparatus includes a robot mounted on an attachment base and movable transversely (X direction), longitudinally (Y direction), and vertically (Z direction) of the automotive body by respective driver mechanisms. The robot is also swingable to meet the toe-in angle (.theta.) and the camber angle (.gamma.) of a hub. The robot is thus singly capable of performing various phases of operation ranging from the detection of the hub position to the attachment of a wheel to the hub.
In the conventional apparatus, the wheels are installed on the automotive body with the hubs (automotive body) used as a positional reference, except when the hub bolts are phased. Therefore, the robot must be angularly moved in the X, Y, Z directions and also in directions to meet the toe-in angle (.theta.) and the camber angle (.gamma.). As a result, the apparatus requires a total of six control axes about which the robot should rotate, resulting in a complex mechanism and a lower degree of reliability.